Rollup of 4 pull requests
Successful merges:
- #85506 (Reset "focusedByTab" field when doing another search)
- #85548 (Remove dead toggle JS code)
- #85550 (facepalm: operator precedence fail on my part.)
- #85555 (Check for more things in THIR unsafeck)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Adjust self-type check to require equality
When we encounter `SomeType::<X>::foo`, `self_ty` is `SomeType<X>` and the method is defined in an impl on `SomeType<A>`. Previously, we required simply that `self_ty <: impl_ty`, but this is too lax: we should require equality in order to use the method. This was found as part of unrelated work on never type stabilization, but also fixes one of the wf test cases.
Fix missing lifetimes diagnostics after #83759
In #83759 while rebasing I didn't realize there was a new function for suggesting to add lifetime arguments. It relied on some invariants, namely that if a generic type/trait has angle brackets then it must have some generic argument, which is now no longer true. This PR updates that function to handle the new invariants.
This also adds a new regression test but I'm not sure if that's the correct place for it.
Fixes#85347
impl FromStr for proc_macro::Literal
Note that unlike `impl FromStr for proc_macro::TokenStream`, this impl does not permit whitespace or comments. The input string must consist of nothing but your literal.
- `"1".parse::<Literal>()` ⟶ ok
- `"1.0".parse::<Literal>()` ⟶ ok
- `"'a'".parse::<Literal>()` ⟶ ok
- `"\"\n\"".parse::<Literal>()` ⟶ ok
- `"0 1".parse::<Literal>()` ⟶ LexError
- `" 0".parse::<Literal>()` ⟶ LexError
- `"0 ".parse::<Literal>()` ⟶ LexError
- `"/* comment */0".parse::<Literal>()` ⟶ LexError
- `"0/* comment */".parse::<Literal>()` ⟶ LexError
- `"0// comment".parse::<Literal>()` ⟶ LexError
---
## Use case
```rust
let hex_int: Literal = format!("0x{:x}", int).parse().unwrap();
```
The only way this is expressible in the current API is significantly worse.
```rust
let hex_int = match format!("0x{:x}", int)
.parse::<TokenStream>()
.unwrap()
.into_iter()
.next()
.unwrap()
{
TokenTree::Literal(literal) => literal,
_ => unreachable!(),
};
```
std: Attempt again to inline thread-local-init across crates
Issue #25088 has been part of `thread_local!` for quite some time now.
Historical attempts have been made to add `#[inline]` to `__getit`
in #43931, #50252, and #59720, but these attempts ended up not landing
at the time due to segfaults on Windows.
In the interim though with `const`-initialized thread locals AFAIK this
is the only remaining bug which is why you might want to use
`#[thread_local]` over `thread_local!`. As a result I figured it was
time to resubmit this and see how it fares on CI and if I can help
debugging any issues that crop up.
Closes#25088
Set dso_local for more items
Related to https://github.com/rust-lang/rust/pull/83592. (cc `@nagisa)`
Noticed that on x86_64 with `relocation-model: static` `R_X86_64_GOTPCREL` relocations were still generated in some cases. (related: https://github.com/Rust-for-Linux/linux/issues/135; Rust-for-Linux needs these fixes to successfully build)
First time doing anything with LLVM so not sure whether this is correct but the following are some of the things I've tried to convince myself.
## C equivalent
Example from clang which also sets `dso_local` in these cases:
`clang-12 -fno-PIC -S -emit-llvm test.c`
```C
extern int A;
int* a() {
return &A;
}
int B;
int* b() {
return &B;
}
```
```
; ModuleID = 'test.c'
source_filename = "test.c"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
`@A` = external dso_local global i32, align 4
`@B` = dso_local global i32 0, align 4
; Function Attrs: noinline nounwind optnone uwtable
define dso_local i32* `@a()` #0 {
ret i32* `@A`
}
; Function Attrs: noinline nounwind optnone uwtable
define dso_local i32* `@b()` #0 {
ret i32* `@B`
}
attributes #0 = { noinline nounwind optnone uwtable "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" "unsafe-fp-math"="false" "use-soft-float"="false" }
!llvm.module.flags = !{!0}
!llvm.ident = !{!1}
!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{!"clang version 12.0.0 (https://github.com/llvm/llvm-project/ b978a93635b584db380274d7c8963c73989944a1)"}
```
`clang-12 -fno-PIC -c test.c`
`objdump test.o -r`:
```
test.o: file format elf64-x86-64
RELOCATION RECORDS FOR [.text]:
OFFSET TYPE VALUE
0000000000000006 R_X86_64_64 A
0000000000000016 R_X86_64_64 B
RELOCATION RECORDS FOR [.eh_frame]:
OFFSET TYPE VALUE
0000000000000020 R_X86_64_PC32 .text
0000000000000040 R_X86_64_PC32 .text+0x0000000000000010
```
## Comparison to pre-LLVM 12 output
`rustc --emit=obj,llvm-ir --target=x86_64-unknown-none-linuxkernel --crate-type rlib test.rs`
```Rust
#![feature(no_core, lang_items)]
#![no_core]
#[lang="sized"]
trait Sized {}
#[lang="sync"]
trait Sync {}
#[lang = "drop_in_place"]
pub unsafe fn drop_in_place<T: ?Sized>(_: *mut T) {}
impl Sync for i32 {}
pub static STATIC: i32 = 32;
extern {
pub static EXT_STATIC: i32;
}
pub fn a() -> &'static i32 {
&STATIC
}
pub fn b() -> &'static i32 {
unsafe {&EXT_STATIC}
}
```
`objdump test.o -r`
nightly-2021-02-20 (rustc target is `x86_64-linux-kernel`):
```
RELOCATION RECORDS FOR [.text._ZN4test1a17h1024ba65f3424175E]:
OFFSET TYPE VALUE
0000000000000007 R_X86_64_32S _ZN4test6STATIC17h3adc41a83746c9ffE
RELOCATION RECORDS FOR [.text._ZN4test1b17h86a6a80c1190ac8dE]:
OFFSET TYPE VALUE
0000000000000007 R_X86_64_32S EXT_STATIC
```
nightly-2021-05-10:
```
RELOCATION RECORDS FOR [.text._ZN4test1a17he846f03bf37b2d20E]:
OFFSET TYPE VALUE
0000000000000007 R_X86_64_GOTPCREL _ZN4test6STATIC17h5a059515bf3d4968E-0x0000000000000004
RELOCATION RECORDS FOR [.text._ZN4test1b17h7e0f7f80fbd91125E]:
OFFSET TYPE VALUE
0000000000000007 R_X86_64_GOTPCREL EXT_STATIC-0x0000000000000004
```
This PR:
```
RELOCATION RECORDS FOR [.text._ZN4test1a17he846f03bf37b2d20E]:
OFFSET TYPE VALUE
0000000000000007 R_X86_64_32S _ZN4test6STATIC17h5a059515bf3d4968E
RELOCATION RECORDS FOR [.text._ZN4test1b17h7e0f7f80fbd91125E]:
OFFSET TYPE VALUE
0000000000000007 R_X86_64_32S EXT_STATIC
```
Fix escape handling
Currently, when we press Escape while on the search results, nothing is happening, this PR fixes it.
More information: it's because in case the element doesn't exist, `hasClass` will return `null`, which coerces into `false` with the `!` comparison operator. But even if it returned `false`, it would still be an issue because if the element doesn't exist, it means it's hidden so in this case it's just as good, hence the additional check I added.
r? ``@jsha``
Implement the new desugaring from `try_trait_v2`
~~Currently blocked on https://github.com/rust-lang/rust/issues/84782, which has a PR in https://github.com/rust-lang/rust/pull/84811~~ Rebased atop that fix.
`try_trait_v2` tracking issue: https://github.com/rust-lang/rust/issues/84277
Unfortunately this is already touching a ton of things, so if you have suggestions for good ways to split it up, I'd be happy to hear them. (The combination between the use in the library, the compiler changes, the corresponding diagnostic differences, even MIR tests mean that I don't really have a great plan for it other than trying to have decently-readable commits.
r? `@ghost`
~~(This probably shouldn't go in during the last week before the fork anyway.)~~ Fork happened.
Issue #25088 has been part of `thread_local!` for quite some time now.
Historical attempts have been made to add `#[inline]` to `__getit`
in #43931, #50252, and #59720, but these attempts ended up not landing
at the time due to segfaults on Windows.
In the interim though with `const`-initialized thread locals AFAIK this
is the only remaining bug which is why you might want to use
`#[thread_local]` over `thread_local!`. As a result I figured it was
time to resubmit this and see how it fares on CI and if I can help
debugging any issues that crop up.
Closes#25088
Rollup of 7 pull requests
Successful merges:
- #84587 (rustdoc: Make "rust code block is empty" and "could not parse code block" warnings a lint (`INVALID_RUST_CODEBLOCKS`))
- #85280 (Toggle-wrap items differently than top-doc.)
- #85338 (Implement more Iterator methods on core::iter::Repeat)
- #85339 (Report an error if a lang item has the wrong number of generic arguments)
- #85369 (Suggest borrowing if a trait implementation is found for &/&mut <type>)
- #85393 (Suppress spurious errors inside `async fn`)
- #85415 (Clean up remnants of BorrowOfPackedField)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Suggest borrowing if a trait implementation is found for &/&mut <type>
This pull request fixes#84973 by suggesting to borrow if a trait is not implemented for some type `T`, but it is for `&T` or `&mut T`. For instance:
```rust
trait Ti {}
impl<T> Ti for &T {}
fn foo<T: Ti>(_: T) {}
trait Tm {}
impl<T> Tm for &mut T {}
fn bar<T: Tm>(_: T) {}
fn main() {
let a: i32 = 5;
foo(a);
let b: Box<i32> = Box::new(42);
bar(b);
}
```
gives, on current nightly:
```
error[E0277]: the trait bound `i32: Ti` is not satisfied
--> t2.rs:11:9
|
3 | fn foo<T: Ti>(_: T) {}
| -- required by this bound in `foo`
...
11 | foo(a);
| ^ the trait `Ti` is not implemented for `i32`
error[E0277]: the trait bound `Box<i32>: Tm` is not satisfied
--> t2.rs:14:9
|
7 | fn bar<T: Tm>(_: T) {}
| -- required by this bound in `bar`
...
14 | bar(b);
| ^ the trait `Tm` is not implemented for `Box<i32>`
error: aborting due to 2 previous errors
```
whereas with my changes, I get:
```
error[E0277]: the trait bound `i32: Ti` is not satisfied
--> t2.rs:11:9
|
3 | fn foo<T: Ti>(_: T) {}
| -- required by this bound in `foo`
...
11 | foo(a);
| ^
| |
| expected an implementor of trait `Ti`
| help: consider borrowing here: `&a`
error[E0277]: the trait bound `Box<i32>: Tm` is not satisfied
--> t2.rs:14:9
|
7 | fn bar<T: Tm>(_: T) {}
| -- required by this bound in `bar`
...
14 | bar(b);
| ^
| |
| expected an implementor of trait `Tm`
| help: consider borrowing mutably here: `&mut b`
error: aborting due to 2 previous errors
```
In my implementation, I have added a "blacklist" to make these suggestions flexible. In particular, suggesting to borrow can interfere with other suggestions, such as to add another trait bound to a generic argument. I have tried to configure this blacklist to cause the least amount of test case failures, i.e. to model the current behavior as closely as possible (I only had to change one existing test case, and this change was quite clearly an improvement).
Report an error if a lang item has the wrong number of generic arguments
This pull request fixes#83893. The issue is that the lang item code currently checks whether the lang item has the correct item kind (e.g. a `#[lang="add"]` has to be a trait), but not whether the item has the correct number of generic arguments.
This can lead to an "index out of bounds" ICE when the compiler tries to create more substitutions than there are suitable types available (if the lang item was declared with too many generic arguments).
For instance, here is a reduced ("reduced" in the sense that it does not trigger additional errors) version of the example given in #83893:
```rust
#![feature(lang_items,no_core)]
#![no_core]
#![crate_type="lib"]
#[lang = "sized"]
trait MySized {}
#[lang = "add"]
trait MyAdd<'a, T> {}
fn ice() {
let r = 5;
let a = 6;
r + a
}
```
On current nightly, this immediately causes an ICE without any warnings or errors emitted. With the changes in this PR, however, I get no ICE and two errors:
```
error[E0718]: `add` language item must be applied to a trait with 1 generic argument
--> pr-ex.rs:8:1
|
8 | #[lang = "add"]
| ^^^^^^^^^^^^^^^
9 | trait MyAdd<'a, T> {}
| ------- this trait has 2 generic arguments, not 1
error[E0369]: cannot add `{integer}` to `{integer}`
--> pr-ex.rs:14:7
|
14 | r + a
| - ^ - {integer}
| |
| {integer}
error: aborting due to 2 previous errors
Some errors have detailed explanations: E0369, E0718.
For more information about an error, try `rustc --explain E0369`.
```
Unify Regions with RegionVids in UnificationTable
A few test output changes; might be able to revert those but figured I would open this for perf and comments.
r? `@nikomatsakis`
# Stabilization report
## Summary
This stabilizes using macro expansion in key-value attributes, like so:
```rust
#[doc = include_str!("my_doc.md")]
struct S;
#[path = concat!(env!("OUT_DIR"), "/generated.rs")]
mod m;
```
See the changes to the reference for details on what macros are allowed;
see Petrochenkov's excellent blog post [on internals](https://internals.rust-lang.org/t/macro-expansion-points-in-attributes/11455)
for alternatives that were considered and rejected ("why accept no more
and no less?")
This has been available on nightly since 1.50 with no major issues.
## Notes
### Accepted syntax
The parser accepts arbitrary Rust expressions in this position, but any expression other than a macro invocation will ultimately lead to an error because it is not expected by the built-in expression forms (e.g., `#[doc]`). Note that decorators and the like may be able to observe other expression forms.
### Expansion ordering
Expansion of macro expressions in "inert" attributes occurs after decorators have executed, analogously to macro expressions appearing in the function body or other parts of decorator input.
There is currently no way for decorators to accept macros in key-value position if macro expansion must be performed before the decorator executes (if the macro can simply be copied into the output for later expansion, that can work).
## Test cases
- https://github.com/rust-lang/rust/blob/master/src/test/ui/attributes/key-value-expansion-on-mac.rs
- https://github.com/rust-lang/rust/blob/master/src/test/rustdoc/external-doc.rs
The feature has also been dogfooded extensively in the compiler and
standard library:
- https://github.com/rust-lang/rust/pull/83329
- https://github.com/rust-lang/rust/pull/83230
- https://github.com/rust-lang/rust/pull/82641
- https://github.com/rust-lang/rust/pull/80534
## Implementation history
- Initial proposal: https://github.com/rust-lang/rust/issues/55414#issuecomment-554005412
- Experiment to see how much code it would break: https://github.com/rust-lang/rust/pull/67121
- Preliminary work to restrict expansion that would conflict with this
feature: https://github.com/rust-lang/rust/pull/77271
- Initial implementation: https://github.com/rust-lang/rust/pull/78837
- Fix for an ICE: https://github.com/rust-lang/rust/pull/80563
## Unresolved Questions
~~https://github.com/rust-lang/rust/pull/83366#issuecomment-805180738 listed some concerns, but they have been resolved as of this final report.~~
## Additional Information
There are two workarounds that have a similar effect for `#[doc]`
attributes on nightly. One is to emulate this behavior by using a limited version of this feature that was stabilized for historical reasons:
```rust
macro_rules! forward_inner_docs {
($e:expr => $i:item) => {
#[doc = $e]
$i
};
}
forward_inner_docs!(include_str!("lib.rs") => struct S {});
```
This also works for other attributes (like `#[path = concat!(...)]`).
The other is to use `doc(include)`:
```rust
#![feature(external_doc)]
#[doc(include = "lib.rs")]
struct S {}
```
The first works, but is non-trivial for people to discover, and
difficult to read and maintain. The second is a strange special-case for
a particular use of the macro. This generalizes it to work for any use
case, not just including files.
I plan to remove `doc(include)` when this is stabilized. The
`forward_inner_docs` workaround will still compile without warnings, but
I expect it to be used less once it's no longer necessary.
This adds a new lint to `rustc` that is used in rustdoc when a code
block is empty or cannot be parsed as valid Rust code.
Previously this was unconditionally a warning. As such some
documentation comments were (unknowingly) abusing this to pass despite
the `-Dwarnings` used when compiling `rustc`, this should not be the
case anymore.
Parse unnamed fields of struct and union type
Added the `unnamed_fields` feature gate.
This is a prototype of [RFC 2102](https://github.com/rust-lang/rust/issues/49804), so any suggestions are greatly appreciated.
r? `@petrochenkov`
